Alkaline earth metal titanates ATiO
3 (A: Mg, Ca, Sr, Ba) were prepared from two types of layered potassium titanates [K
2Ti
2O
5 and K
0.6Ti
1.85O
4 (hereafter, Lss)] by using alkaline earth metal molten salts [ACl
2 + A(NO
3)
2 (1:1)]. For A = Ca a single phase of perovskite-type compound was prepared at 600°C by using both starting compounds and the reaction temperature was lower than in 400°C that of the solid state reaction with TiO
2 (anatase) and CaCO
3. A single phase of perovskite-type SrTiO
3 was obtained at 600 and 700°C for K
2Ti
2O
5 and Lss, respectively and these temperatures were much lower than that (1200°C) of the solid state reaction with TiO
2 (anatase) and SrCO
3. In the case of perovskite-type BaTiO
3 a single phase of perovskite-type compound was prepared at 700°C by using both starting compounds and also this temperature was much lower than that (above 1300°C) of the solid state reaction with TiO
2 (anatase) and BaCO
3. Although neither K
2Ti
2O
5 nor Lss could produce a single phase of ilmenite-type MgTiO
3, it was prepared by the solid state reaction with TiO
2 (anatase) and magnesium basic carbonate at 900°C. A single phase of ilmenite-type CdTiO
3 was prepared from K
2Ti
2O
5 by using cadmium molten salts [CdCl
2 + Cd(NO
3)
2 (1:1)] at 500°C. By taking account of the fact that ilmenite-type CdTiO
3 transforms to perovskite-type structure, this preparative method using layered potassium titanates with molten salts preferred to crystallize perovskite-type titanates at lower temperature rather than ilmenite-type ones.
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